CppEditor: Make "Add curly braces" quickfix more robust

Anchor the opening brace at the closing parenthesis, rather than at the
statement. This way, we won't get troubled by macro weirdness in the
statement part.

Fixes: QTCREATORBUG-13921
Change-Id: I05af24d1642e6b62c78bb2f47a1ef0b1fea326d0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/cppeditor/cppeditorplugin.h

@@ -197,6 +197,8 @@ private slots:
     void test_quickfix_ExtractLiteralAsParameter_memberFunction_separateFiles();
     void test_quickfix_ExtractLiteralAsParameter_notTriggeringForInvalidCode();
 
+    void test_quickfix_addCurlyBraces();
+
     void test_quickfix_InsertVirtualMethods_data();
     void test_quickfix_InsertVirtualMethods();
     void test_quickfix_InsertVirtualMethods_implementationFile();

src/plugins/cppeditor/cppquickfix_test.cpp

@@ -5417,6 +5417,31 @@ void CppEditorPlugin::test_quickfix_ExtractLiteralAsParameter_notTriggeringForIn
     QuickFixOperationTest(testDocuments, &factory);
 }
 
+void CppEditorPlugin::test_quickfix_addCurlyBraces()
+{
+    QList<QuickFixTestDocument::Ptr> testDocuments;
+    const QByteArray original = R"delim(
+void MyObject::f()
+{
+    @if (true)
+        emit mySig();
+}
+)delim";
+    const QByteArray expected = R"delim(
+void MyObject::f()
+{
+    if (true) {
+        emit mySig();
+    }
+}
+)delim";
+
+    testDocuments << QuickFixTestDocument::create("file.cpp", original, expected);
+    AddBracesToIf factory;
+    QuickFixOperationTest(testDocuments, &factory);
+
+}
+
 void CppEditorPlugin::test_quickfix_ConvertQt4Connect_connectOutOfClass()
 {
     QByteArray prefix =

src/plugins/cppeditor/cppquickfixes.cpp

@@ -691,7 +691,8 @@ namespace {
 class AddBracesToIfOp: public CppQuickFixOperation
 {
 public:
-    AddBracesToIfOp(const CppQuickFixInterface &interface, int priority, StatementAST *statement)
+    AddBracesToIfOp(const CppQuickFixInterface &interface, int priority,
+                    const IfStatementAST *statement)
         : CppQuickFixOperation(interface, priority)
         , _statement(statement)
     {
@@ -705,10 +706,10 @@ public:
 
         ChangeSet changes;
 
-        const int start = currentFile->endOf(_statement->firstToken() - 1);
+        const int start = currentFile->endOf(_statement->rparen_token);
         changes.insert(start, QLatin1String(" {"));
 
-        const int end = currentFile->endOf(_statement->lastToken() - 1);
+        const int end = currentFile->endOf(_statement->statement->lastToken() - 1);
         changes.insert(end, QLatin1String("\n}"));
 
         currentFile->setChangeSet(changes);
@@ -717,7 +718,7 @@ public:
     }
 
 private:
-    StatementAST *_statement;
+    const IfStatementAST * const _statement;
 };
 
 } // anonymous namespace
@@ -731,7 +732,7 @@ void AddBracesToIf::match(const CppQuickFixInterface &interface, QuickFixOperati
     IfStatementAST *ifStatement = path.at(index)->asIfStatement();
     if (ifStatement && interface.isCursorOn(ifStatement->if_token) && ifStatement->statement
         && !ifStatement->statement->asCompoundStatement()) {
-        result << new AddBracesToIfOp(interface, index, ifStatement->statement);
+        result << new AddBracesToIfOp(interface, index, ifStatement);
         return;
     }
 
@@ -742,7 +743,7 @@ void AddBracesToIf::match(const CppQuickFixInterface &interface, QuickFixOperati
         if (ifStatement && ifStatement->statement
             && interface.isCursorOn(ifStatement->statement)
             && !ifStatement->statement->asCompoundStatement()) {
-            result << new AddBracesToIfOp(interface, index, ifStatement->statement);
+            result << new AddBracesToIfOp(interface, index, ifStatement);
             return;
         }
     }